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naproxen

(Encyclopedia)naproxen and naproxen sodium, potent nonsteroidal anti-inflammatory drugs (NSAID) used to alleviate the minor pain of arthritis, menstruation, headaches, and the like, and to reduce fever. Along with ...

formic acid

(Encyclopedia)formic acid or methanoic acid mĕthˌənōˈĭk [key], HCO2H, a colorless, corrosive liquid with a sharp odor; it boils at 100.7℃ and solidifies at 8.4℃. It has the lowest molecular weight and is ...

flame test

(Encyclopedia)flame test, test used in the identification of certain metals. It is based on the observation that light emitted by any element gives a unique spectrum when passed through a spectroscope. When a salt ...

viscose process

(Encyclopedia)viscose process vĭsˈkōs [key], method widely used for the commercial preparation of rayon. Cellulose, prepared from either wood pulp or, less commonly, cotton linters, is treated with sodium hydrox...

cesium

(Encyclopedia)cesium sēˈzēəm [key] [Lat.,=bluish gray], a metallic chemical element; symbol Cs; at. no. 55; at. wt. 132.90545; m.p. 28.4℃; b.p. 669.3℃; sp. gr. 1.873 at 20℃; valence +1. Cesium is a ductil...

mercury, chemical element

(Encyclopedia)mercury or quicksilver [from the Roman god Mercury], metallic chemical element; symbol Hg [Lat. hydrargyrum=liquid silver]; at. no. 80; at. wt. 200.59; m.p. −38.842℃; b.p. 356.58℃; sp. gr. 13.55...

saccharin

(Encyclopedia)saccharin săkˈərĭn [key], C7H5NSO3, white, crystalline, aromatic compound. It was discovered accidentally by I. Remsen and C. Fahlberg in 1879. Pure saccharin tastes several hundred times as sweet...

dissociation

(Encyclopedia)dissociation, in chemistry, separation of a substance into atoms or ions. Thermal dissociation occurs at high temperatures. For example, hydrogen molecules (H2) dissociate into atoms (H) at very high ...

alkali metals

(Encyclopedia)alkali metals, metals found in Group 1 of the periodic table. Compared to other metals they are soft and have low melting points and densities. Alkali metals are powerful reducing agents and form univ...

concentration

(Encyclopedia)concentration, in chemistry, measure of the relative proportions of two or more quantities in a mixture. The concentration of a solute is very important in studying chemical reactions because it deter...